Carotid body remodelling in l-NAME-induced hypertension in the rat.

The carotid body (CB) is a chemoreceptor organ located at the bifurcation of the common carotid artery. It is made up of the carotid glomus, a structure containing type 1 cells surrounded by type 2 cells. The aim of this study was to evaluate the morphological changes of the CB and carotid glomus in the rat model of l-NAME-induced hypertension. Male Wistar rats were divided in two groups: control untreated rats (C) and rats receiving l-NAME 40 mg/kg/day (LN) for 6 weeks. At the end of the experiment, the systolic blood pressure was 63% higher in the LN group compared with the C group. Morphometric analysis showed that the area of the CB was 29% greater in the LN group compared with the C group. The density of nuclei in the CB was similar between groups, but it was 31% less in the carotid glomus of the LN group. Cells in the CB of the LN group displayed cytoplasmic vacuolation and expressed several biogenic amines. There were more elastic fibres, proteoglycans and collagen fibres in the LN group compared with the C group. Immunohistochemistry showed increased expression of nuclear factor kB, substance P, vascular endothelial growth factor and neuronal nitric oxide synthase in the LN group, while expression of the protein gene product 9.5 was decreased. l-NAME alters cell morphology and the expression of extracellular matrix molecules in the CB and carotid glomus in rats with l-NAME-induced hypertension.

Prevalence of genital human papillomavirus infections established using different diagnostic techniques among males attending a urological clinic.

OBJECTIVE: To compare the accuracy of different diagnostic methods and their use in estimating the prevalence of genital human papillomavirus (HPV) infections in males attending a urological clinic. MATERIAL AND METHODS: The study population was derived from a series of 1,153 consecutive males attending a urological clinic in São Paulo between January 1996 and November 1998. Of these 1,153 males, 334 had clinically suspected genital HPV infection and comprised the study cohort. The diagnostic methods used included peniscopy, directed biopsy and HPV detection by means of the Hybrid Capture 2 (HC) assay for both oncogenic and non-oncogenic HPV types. RESULTS: Peniscopy was performed for 297 males, positive results being reported in 237 cases (79.8%). Directed biopsy was performed in 188 males, and histology suggested HPV in 140 of these cases (74.5%). HC confirmed the presence of HPV in only 35.2% of the histologically HPV-suggestive cases. Peniscopy has good sensitivity for identifying male carriers of genital HPV. However, the technique has an inherent low specificity, limiting its usefulness to the correct identification of those who never present with HPV infection. Characteristic histological alterations are useful in suggesting HPV infection, but their correlation with HPV detection using HC is not particularly good. CONCLUSIONS: These data suggest that both histology and peniscopy have low specificity in detecting male genital HPV. Accurate diagnosis of HPV infection can be confirmed by molecular detection methods only. Histology, however, plays an important role in the differential diagnosis. An appropriate diagnostic protocol for male genital HPV infections in a urological clinic should include peniscopy, histology and molecular diagnostic tools (HC or polymerase chain reaction).

Primary headache care delivery by nonspecialists in Brazil. Brazilian Headache Care Cooperative Group.

Headaches are common disorders usually examined by nonneurologists. In order to assess how primary headache patients (IHS groups 1, 2, and 3) are generally managed by nonspecialists, 414 patients were asked about their previous headache care. Correct diagnosis had previously been made in only 44.9%, 6.7%, and 26.7% of the migraine, tension-type headache, and cluster headache patients, respectively. The patients underwent 501 investigative procedures motivated by the headache, averaging 1.21 examinations per patient, mostly EEGs. Preventive treatment was largely overlooked irrespective of the headache type. It is concluded that scientific improvements in headache care may be ineffective unless educational programs improve headache knowledge in general.

Connective tissue accumulation in the muscle layer in normal and varicose saphenous veins.

Varicose veins alternate areas of phlebosclerosis and hypertrophy of the vein wall. In this study, samples of long saphenous veins obtained from patients submitted for aortocoronary saphenous vein graft or for surgical resection of varicose saphenous veins were examined. Histologic changes in the intima, muscle, and adventitial layers were quantified. Thicknesses of the venous wall layers were obtained by linear measurements, and the volumetric density of the connective tissue in the muscle layer was determined by point counting. The muscle layer thickness was 300 +/- 13 and 581 +/- 25 microns in normal and varicose veins, respectively. A more severe connective tissue accumulation within the muscle bundles was found in the varicose condition. The volumetric density of the connective tissue in the circular muscle layer (CmC/MmC) showed also a marked difference between varicose (0.67 +/- 0.08) and normal veins (0.43 +/- 0.02), P < 0.05. The authors suggest that the varicose condition is associated with a connective tissue uniform accumulation among muscle cells in the circular muscle layer.

[Histochemical study of elastic system fibers of the walls of normal and pathological saphenous veins]. / Etude histochimique des fibres du système élastique dans les parois des veines saphènes normales et pathologiques.

Normal, varicose and phlebitic saphenous veins were studied by histochemical methods to establish the qualitative variations of their structural components. The histologic preparations were stained by hematoxylin-eosin Gomori's trichrome, orcinol-neofuchsin and resorcin-fuchsin. Normal saphenous vein showed two layers of smooth muscle cells--an internal circular and an external longitudinal. The components of the elastic system were found in the three layers. Elastic fibers were present in the adventitia under an elongated and wavy conformation. In the media they were present in the external portion. Elaunin fibers were found in the media and intima. The oxytalan fibers were not consistently found. The media and intima of varicose veins showed contracted smooth muscle cells associated with fragmented elastic fibers and augmentation of elaunin fibers. In cases of thrombophlebitis the same alterations observed in varicose veins were found together with a decrease of elastic system fibers in the media and intima. The muscle cells showed a loss of their morphologic characteristics.

[Bilateral abducens nerve palsy in nasopharyngeal carcinoma]. / Paralisia bilateral do abducente em carcinoma de nasofaringe.

We report a case of bilateral abducens palsy as initial finding in nasopharyngeal carcinoma. Possible mode of involvement is discussed. Only one case has been reported in the past.